85865-58-3Relevant academic research and scientific papers
4, 5-DIHYDRO-LH-PYRAZOLE COMPOUNDS AND THEIR PHARMACEUTICAL USES
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Page/Page column 65, (2010/11/03)
Mineralocorticoid receptor antagonists (MRa), pharmaceutical compositions containing such inhibitors and the use of such inhibitors to treat, for example, diabetic nephropathy and hypertension in mammals, including humans.
Alkyliron and Alkylcobalt Reagents, VIII. - Alkyl-Iron(II) Compounds as Reagents and Catalysts for the Transformation of Acyl Chlorides into Ketones
Kauffmann, Thomas,Voss, Karl-Uwe,Neiteler, Gabriele
, p. 1453 - 1460 (2007/10/02)
Me2Fe, Bu2Fe, Me3FeLi, or Bu3FeLi - prepared in situ by reduction of FeCl3 to FeCl2 and subsequent alkylation with MeLi, MeMgBr, BuLi, or BuMgBr - are useful reagents for the conversion of acyl chlorides into ketones.The system (RMgX + catalytic amount of FeCl3) react like the FeII reagents with acyl chlorides to give ketones even at -65 deg C.Competition experiments with benzoyl chloride/2-methoxybenzoyl chloride show that the selectivity increases (competition constants Kk = 9.9, 10.7, 10.9, 15.0, ca. 110) in the sequence MeFeCl, Me2Fe, Me3Fe(MgBr), Me4Fe(MgBr)2, and catalytic system (MeMgBr + 2.5 mol percent FeCl3) (= 2, 3, 4, 5, and 40MeMgBr per 1 FeCl3, respectively).A new hypothesis on the nature of the active catalyst is discussed. Key Words: Organoiron compounds / Iron catalysts / Ketone synthesis
Arene-Metal Complex in Organic Synthesis: Directed Regioselective Lithiation of (?-Substituted benzene)chromium Tricarbonyl Complexes
Uemura, Motokazu,Nishikawa, Naomi,Take, Kazuhiko,Ohnishi, Masato,Hirotsu, Ken,et al.
, p. 2349 - 2356 (2007/10/02)
(3-Methoxybenzyl alcohol)chromium tricarbonyl complex (8) and (2-substituted 7-methoxy-1-tetralol)chromium complexes 14-17 are selectively lithiated at the 4-position and 6-position, respectively, by treatment with n-BuLi/TMEDA.The regioselectivity of this lithiation is improved with increasing bulk of the butyllithium reagent employed.Since the direct lithiation of the corresponding chromium-free arenes normally proceeds at the 2- and 8-positions, complementarily substituted arenes can be prepared by using chromium tricarbonyl complexes.The different lithiation is explained by the relative configuration of the chromium tricarbonyl group in the (?-arene)Cr(CO)3 complexes and the electrostatic factor.This rationalization is supported, at least in part, by X-ray crystallography of the complex 16.On the other hand, the chromium complexes of arenes without a free hydroxyl group, such as benzyl methyl ether or ethylene acetals of benzaldehydes, are lithiated at the 2-position preferentially.
